A rising generation time KPI metric is a bad measurement #15820

The KPI Widget does a comparation with data collected during the period.
Mostly, having a rising increment is good (green dot), but sometimes having an increment is bad (red dot), for example: generation time.

in this screenshot, generation time report should display red dots and red notations when generation time raises, the opposite, related to the search kpi metric widget.

For some metrics, is difficult to say when it's good or bad... Bounce rate, for example, maybe is good or bad, it depends by the page. Searches metrics, maybe is good when is going down, meaning people is using less the search engine to find content...

Maybe can be useful having a switch in each widget, declaring when we want green for rising metrics and when we want green for lowering metrics?

There is an event Metrics.isLowerValueBetter, which can be used to define that. In some cases that might not be done correctly.

Note: the page generation time will be deprecated in Matomo 4 and replaced with more specific metrics. See #15736